Research On Mechanical Design And Opto-Mechanical Integration Of Vehicle 3d Imaging Laser Radar

With the development of laser distance measuring technology,laser radar has been widely used for its advantage of high resolution and precision,strong anti-interference ability,small volume and light weight.And vehicle 3D Imaging laser radar is widely used in the fields of 3D city modeling,terrain mapping,agroforestry ecosystem,military detection,unmanned driving and robot obstacle avoidance and navigation with the advantages of the vehicle-mounted platform.Based on the design performance requirements of the radar,the dynamic and thermodynamic analysis of mechanical structure of the radar are carried out.And the influence of the vibration environment and the temperature change on the accuracy of radar is calculated.Finally,the assembly and debugging of the radar system are completed.The main research contents are as follows:1.Structure design of vehicle lidar.According to the operating principle of vehicle 3D imaging lidar,the composition of system is determined and the modules needed are selected.The vehicle 3D imaging lidar adopts the rotating structure with scanning mirror,which has small space occupation,high reliability and strong stability.The structure design of vehicle 3D imaging lidar is based on the principle of optimizing spatial layout and enhancing heat dissipation ability to arrange each module.In addition,balancing design has been carried on the rotating parts of vehicle 3D imaging lidar based on the dynamic balance theory.2.Dynamics,thermodynamics and accuracy analysis of vehicle lidar system.Modal analysis,harmonic response analysis,random vibration analysis and thermal analysis are carried out by ANSYS Workbench toolbox.Through the modal analysis and harmonious response analysis of the vehicle lidar structure,the natural frequency and vibration mode of the vehicle lidar are obtained.In this way,the resonance point of the system is avoided,which has verified the rationality of the structure.Through the random vibration analysis and thermal analysis of the structure,the influence of random vibration and temperature change on the deformation of the vehicle lidar structure is obtained.And the influence of the deformation of the opto-mechanical structure on the laser exit angle and the deflection of the optical axis is analyzed.In the process of analyzing the influence of thermal deformation on the accuracy of vehicle lidar,the optimization measures of opto-mechanical structure are put forward,and the feasibility of the optimization measures is verified by comparing the deformation of opto-mechanical structure before and after optimization.Seeing from the results of thermal simulation,we can conclude that the optimized optical structure meets the accuracy requirement of ±0.1mrad for the laser exit angle deviation of the vehicle lidar system.3.Installation and adjustment of vehicle 3D imaging lidar system.Assembly and debugging of the system are also an important factor affecting the measurement accuracy of vehicle lidar,especially the installation and adjustment of optical path structure.In this paper,the optical path installation and adjustment scheme of vehicle 3D imaging lidar has been designed.At the same time,the adjustment of laser collimation,coaxiality of optical path,motor rotating shaft and scanning mirror has also been completed.Finally,after completing the light tuning of the vehicle 3D imaging lidar,the whole structure of the vehicle lidar is assembled.